Method of selection in systems of communication.



Specicat'an of Letfewaent Pap'tanijef Nav( 2, 1%@

than; all at once thereby coxmeeting each crfor showing afpair'of'contactscircuits controlled by the rela s arej'metallim.

nected by wires2 and switch s? to the batteryV u B which is grounded asis also the opposite side of therelays'R, R2 R4, etc. The units relaysR", R3, R5 etc. are connected through' the' ten contact pens Prespectively of the switch S whose contact wiper sisconnected throu h tobattery B by the wire s and The switches S and S are similar in. everyrespect andindescribing them I will refer to the lswitch -S because allof the contact pens are utilized whereas with the switch S only threeofthe contact pens are usedin this instance. 'A magnet-m` grounded uponone side is connected tothe battery B through a key K and a wire Je.Pivoted in' proper l relation so as ',tobe magnetiaed. bythe coreZofihemagnet mfis an armature m. n ormally' retracted by a spring m2 andcarrying uson its`fouter end a spring pressed paw1 ma a aptedy and vstepupvthe switch rod m* which carries4 the contact `wiper 8*. `As the rodm4 isns'tepped u it is engaged by a locking pawl m"- provi ed with arearwardly projecting tongue m engaged by the projecting arm m ofthearmature ma. This armature mal is controlled by the-release maget m'.The f operation fof' the switch is; as follows;.Whe-n the keyjKisdepressed, battery current is put-upon the magnet m by the followingcircuit: battery, k', K wire magnet m, and ground.- The magnet thusenergized attracts-its armature m and throws the pa'wl m into engagementwith one of the ten teeth ton the rod m* thus stepping1 it up sothattswiper s* contacts with t e first pen in the group P. When the key isreleased the armature m 45 drops back to normal'position and is held outofengagement lwith the teeth by a st t; the rod carrying the wiper s* is.held 1n this position by the locking pawl m until the key K controllin'the release magnet is'- pressed, at this time t e following circuitis'closed: .battery B,i,wire a. ma et m9 and ground. The magnet m" thuseing enerized attracts its armature ms and .throws t e arm intoengagement with the rearwardly projecting tongue m on the locking pawim5. This throws the locking awl out of engagement with the switch ro m*and allow-sit to drop by gravity. It will thus baseer. that any relayconnected through enfite. is then denergized and the cir- .1 contro?.thereby broken.4 Havino 'denine. the operation of the switches I will,cow proceed to describe the vconnection be?" tween the switches and.the diierentxsets of W relays: Between the twoseta of relays a A. byWires2, 4.-' f thef'letterslamb, c, d, e, f, g,h

wires 1, 3, 5, :7, 9,11,.13, 1 5, 17 and 19 mth@ relay "R1, through"battery, lwirej.\z2, w i r a', the'rst contactv 'cable C passes whichiscorn osed of ten pairs of wires which may be' esignated by c, j, whichare connectedg and disposed as follows: All of theqpairs, aresmultipledto the ten pairs of 7o s; contacts on each of the tens relays R, R2 andR2 Thusthe first paira goes to the rst pair of contacts on each of therelays R, R2 `and R4; Thesecond pair b goesto the secf ond pair ofcontacts oneach of these relays',

yand so on. 4The corresponding or coperating contacts of the relays areconnected. to the individual lines or circuits to be selects ed, thus,in the relay R ap ear the terminals of lines #l to #10, in reiJay R2appear the 80 terminals of lines #11' to :$20, and in relay R4 appearthe terminals of ines #21 to #30. Each-of the pairs a, b, c, etc., isconnected to the single pair of contacts. One of the units relays R',RHR5 etc, Thus the pair a appears only in the relay R, and the pair' fappears only in the relay R11, etc. I have shown the contacts of theunits relays coni nected on one Side to a common circuit l2; to which isconnected altelephone Q. I have shown line "#1 which is the firstoutside line on the relay R, connected toa telephone ,Q and it isto beunderstood that all the other l terminals may be connected to similartele-` phones or any desiredapparatus. y 95 The operation of selecting'any one of the# lines represented on the 'tens relays. is as follows:Suppose" it bel desired to connect the telephone O Withthe telephone Q;the line circuit' lleading to Q is #l which'a pears only?` in theterminals on relay hencethef operator presses the key K2 to` step therod with its wiper a', up to the first cmtact'.` pen in thegrou Pf,.thus energizing erjfollowing circuit: 10.5` penr'in the grouli; ,'Wire2 relay R and l ground. 'lfhe' reky-Rhn-pulliig up conmcts all of thellnes #l to #1.0 on to the pairs ofgk.; wires a, b, c, d, etc., in 'thecable R', R3, R, etc., it follows that we have thus connected'the lines:#:l to :#10 to the relays? respectively romjR to R19 and by energizingany one' of these relays we may select 115 any one of tbe-individuallineswhich haveA ythus become connected. In the present instance theoperator closes the key K once thus connecting the battery to the magnetm by the-following circuit: battery B, wire c, 120:

relay R andgroand; and to the relay R 13 ma.. these pairs aredistributed among the relays,

mediate a ency until the unit is found which In testimony whereof I aixmy signature correspond s to the desired unit circulilt in ltlhe inpresence of two Witnesses.A

Segre ate ou maintainn a ot er l grous and 5.11.1 her units in heinterme- EDWARD CLEMENT' date agency disabled, and finally associatingWitnesses:

the selected unit with a sin 1e agency com- E. ElMoNs'mN, Jr.,

mon touall Vthe groups and a the units. JAmzs H. MARR.

